A liquid crystal display (“LCD” for short) is highly favored by engineers due to its characteristics of low power consumption, thin and light appearance and radiation-free and so on, and thus it has been widely used in a variety of electronic devices including electronic products such as a computer, a mobile phone and the like. The liquid crystal display generally comprises an array substrate, a color film substrate and a liquid crystal layer located between the array substrate and the color film substrate, and has mainly the following display principle: rotation angles of liquid crystal molecules in the liquid crystal layer can be changed by changing a potential difference at two ends of the liquid crystal layer, such that light transmittance of the liquid crystal has a change, so as to display different images.
In general, polarities of voltages applied to the two ends of the liquid crystal layer must be reversed every a predetermined time to avoid liquid crystal materials producing polarization and thus causing a permanent damage. There are four common modes of polarity reversal for a pixel array, frame reversal, column reversal, row reversal and dot reversal. Herein, before writing of a previous frame is ended and writing of a next frame is started, it is called as a frame reversal if voltage polarities ΔV (it is defined ΔV=pixel voltage Vpixel−common voltage Vcom) stored in pixels of the whole frame are the same (all of the voltage polarities are positive or negative); it is called as a column reversal if voltage polarities stored in pixels of the same column are the same and voltage polarities stored in pixels of adjacent columns are reverse; it is called as a row reversal if voltage polarities stored in pixels of the same row are the same and voltage polarities stored in pixels of adjacent rows are reverse; it is called as a dot reversal if a voltage polarity stored in each pixel is in reverse to voltage polarities stored in up, down, left and right adjacent pixels. In order to improve the quality of the whole display picture, a pixel dot reversal driving mode has increasingly become a present mainstream driving mode.
In the existing dot reversal driving mode, a data line signal needs to be reversed once within a scanning time for each gate line, so as to implement a dot reverse driving. By adopting such a dot reverse driving mode, since the data line driving voltage has a greatly large voltage swing between positive and negative polarity gray scales, huge power consumption will be caused in the switching process of the positive and negative polarity gray scale voltages.